


Form Follows Function

by Politzania



Category: Captain America (Movies), Iron Man (Movies), Marvel Cinematic Universe
Genre: Anal Fingering, Anal Sex, Armor Kink, Armor appreciation, M/M, Oral Sex, Threesome
Language: English
Status: Completed
Published: 2019-10-04
Updated: 2019-10-04
Packaged: 2020-12-01 20:31:24
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,122
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20890994
Author URL: https://archiveofourown.org/users/Politzania/pseuds/Politzania
Summary: Steve’s appreciation for the technological wonder that is the Iron Man armor turns kinky.Happy Steve Bingo 2019 Fill - Breathless





	Form Follows Function

**Author's Note:**

> Title: Form Follows Function  
Content Creator(s): PoliZ/Politzania  
Happy Steve Bingo Square Filled I1 - Breathless  
Rating: Explicit  
Pairing(s): Steve/Tony/Mark 43 Armor  
Warning(s)/Trigger(s): armor kink, smut,  
Summary: Steve’s appreciation for the technological wonder that is the Iron Man armor turns kinky.

The first time he’d seen Tony putting on the Iron Man suit, it had taken Steve’s breath away. He’d never really given it much thought before, how each piece of the armor had to be precisely placed to mesh with the others and function as a whole. That there were layers below the shining red and gold exterior, mechanical muscles and electric nerves under the metallic skin. Steve had studied anatomy books to improve his life drawing skills, so he had some knowledge of how humans were put together; he marveled at how Tony’s creation mirrored both form and function. 

When it came to the way Tony so effortlessly controlled his high-tech suits, well, Steve had put on the Iron Man helmet once and asked JARVIS to turn on the heads-up display. The barrage of information left Steve with an instant headache and struggling to catch his breath: how could Tony possibly process and react to so much information all at once? 

“You really are a genius,” Steve commented admiringly, watching the automated gantry remove the last few pieces of the armor as Tony strolled along the landing pad. And while Steve admired the Iron Man suits immensely, he loved the man inside them even more.

“What, you didn’t believe it when I told you that way back when, sunshine?” Tony’s teasing reply was a stinging reminder of how poorly their initial meeting had gone. They’d gotten far beyond the harsh accusations, but the reminder made Steve’s suck in a breath as if he could take those hurtful words back. 

“I didn’t know the real you, then,” he countered. “Just the Tony Stark from the gossip rags. That and the SHIELD files.”

Tony snorted and made a face. “Yeah, the whole ‘not recommended’ thing. Did I ever tell you I think Natasha did that on purpose, to see if I’d try to prove she was wrong?” 

“Sounds like something our clever teammate would do.” Steve pulled Tony into an embrace and kissed him until they were both short of breath. “I missed you.” 

“Are you talking to me or the armor?” His lover’s flirtatious grin warmed Steve’s heart. “You know, the Mark 43 in remote command mode could make for a hell of a threesome.” 

Steve had always been a touch too possessive to seriously entertain the thought of having someone join him and Tony in bed. But if the third person weren’t really a separate person, but rather a suit controlled by Tony? Steve’s head spun slightly as his blood rushed in equal measure to his face and his groin. “Please tell me you’re not joking,” he breathed. 

“Well, now I’m not.” Tony’s grin curled into a smirk; he was clearly enjoying the effect his comment had on Steve. “What exactly did you have in mind, hot stuff?” He made a gesture and a gauntlet came speeding over to form itself around one hand. Tony then proceeded to run it down his own body to cup his crotch. “Something like this?” 

“N-no,” Steve stammered, “Me. I wanna... ” The thought of that cool, smooth metal stroking him intimately rendered him nearly speechless. 

Tony’s eyes lit up. “Oh, so you’d rather be the center of attention? I can work with that.” He walked around behind Steve, wrapping the gauntleted arm around his waist to fondle Steve’s hardening cock. “How’s this feel?” 

“More.” 

Tony shifted to slide the gauntlet down between the two of them, pressing a finger beween Steve’s asscheeks through the jeans. “Do you want one of these, deep inside? I know how much you like that, loverboy. Or maybe a strap-on, the suit bending you right over the bed?” Tony’s breath was hot on the back of Steve’s neck.

“Yes, Tony, yes!” Steve groaned, his knees trembling with want. 

“Well then...,” Tony purred before delivering another searing kiss. “Give me, oh, an hour or so to tinker. I -- make that we -- will meet you in our bedroom.” He slapped Steve on the ass with the gauntlet hard enough to make him jump. “Now go get ready.” 

Tony, for once, was right on time. Steve had been trying very hard not to watch the clock after taking a quick, yet thorough shower. He was shifting restlessly from one position to another when the door to the penthouse opened. 

“Honey, I’m home!” Tony called out, “and I brought a friend!” The unmistakable sound of the armor walking across their living room had Steve’s full attention; he’d left the bedroom door open on purpose. Tony entered the room first, wearing a high-tech headset, followed by the gleaming red and gold of his alter ego. 

Tony tossed a bundle on the bed. “Here’s the strap on harness. Pick your dick and we can get started.” His hair was damp; he’d apparently taken advantage of the shower in the workshop’s bathroom. 

Steve dug into the bottom drawer of the nightstand where they kept a few toys to play with, usually when one or the other of them had to be out of town for an extended period. As Steve made a choice and fit the base of the dildo into place on the harness, Tony stripped and slid into bed next to him.

“How about a little twosome foreplay first?” he purred, taking the harness from Steve and handing to the armor before setting the headset aside. 

“You read my mind, sweetheart.” Steve wrapped his arms around Tony, reveling in the feel of his lover’s bare skin against his, while anticipating the addition of cool, smooth metal to the encounter. Their kisses grew heated, hands roaming restlessly over one another, touching and teasing. 

“So, I know what Mark over there,” Tony gestured languidly to the armor, “is going to be doing to you, loverboy, but do I get to play as well? Not that I wouldn’t be happy just to watch, mind you.” 

“Want to suck you off while it’s fingering me open,’” Steve panted, “then fuck you while it fucks me.” 

“Dear god, I love it when you talk dirty.” Tony nipped at Steve’s throat before playfully pushing him downward. “Let’s not waste any time, then.” 

Steve couldn’t resist swirling his tongue around one of Tony’s nipples, but otherwise quickly made his way between his bedmate’s legs. Balancing himself on knees and elbows, Steve shivered in anticipation as the armor came to life once again, picking a bottle of lube out of the drawer before moving to stand behind him. 

Steve glanced up to see a rapt expression on Tony’s face, the headset’s small screen showing the armor’s POV. “You are gorgeous from every damn angle, sunshine. But I’m gonna need you to hold off on the cock-swallowing for a few. Even with the haptic feedback on the gauntlet turned up to eleven, you’ll have to tell me what feels good and what doesn’t, at least at first.” 

Steve couldn’t argue with that logic, even though Tony’s cock was literally beckoning to him, standing stiff and proud just a few inches from his face. He blew gently on it just to make Tony squirm. “Okay, but once we get that figured out, I’m going down on you like there’s no tomorrow.” 

“Deal.” 

Steve squirmed a bit himself as a drizzle of lube slid down his crack, followed by a gentle stroke across his entrance. “More,” he begged; the stroking increased in pressure before one fingertip dipped inside. 

“Like this?” Tony asked, a note of concern in his voice. 

“Yes, just like that.” Steve pushed into the touch, relishing the stretch as the unyielding metal digit slipped further in. It was better than he’d even imagined. “Deeper,” he gasped, arching his back as the finger rocked in and out. “Feels so damn good.” He wrapped his hand around Tony’s cock, as much to ground himself as to share the pleasure he was feeling. 

“You gotta watch this, darling.” Tony murmured. Steve looked up to see the headset’s video feed projected above the headboard. His ass filled the screen, cheeks spread wide as the fisted gauntlet thrust its finger deep inside. Steve groaned as his face flushed in embarassed arousal. 

Tony chuckled. “It’s a beautiful sight, isn’t it?” 

In response, Steve wrapped his lips around the tip of Tony’s cock eagerly. Tony’s gasp of pleasure only fanned the flames of Steve’s desire; he tilted his head so he could swallow Tony down to the root. As he bobbed up and down on Tony’s cock, the gauntlet matched his movements; Steve lost himself in the sensation of being filled on both ends. 

In the middle of a fantasy about the armor holding him down, forcing him to take every last inch of Tony’s cock and not letting go until he blacked out, the gauntlet crooked its finger just so, pressing firmly against his prostate. Steve couldn’t hold back any more, one hand flying back to stroke himself to climax as he deepthroated Tony. The gauntlet stilled as he shook and shuddered through his orgasm.

“How was that, sweetheart?” Tony asked, petting through Steve’s hair as he came up for air. Steve lay his head on his lover’s thigh, wincing slightly as the gauntlet withdrew. 

“Wonderful,” he sighed happily. “But we’re not done yet, are we?” He pressed a kiss to Tony’s thigh as he ran his hand up the other. 

“I was hoping you’d say that,” Tony grinned, eyes alight with passion. “What do you want Mark to do while you’re getting me ready?”

“How about gettin’ me hard again, sugar?” 

“Your wish is our command.” Tony reached over to the nightstand for a second bottle of lube, which he handed to Steve before spreading his legs wider. “Don’t tease me too much, loverboy. I want to be able to hold out awhile.”

As Steve began fingering Tony, the armor took him in hand. Steve gasped as cool metal fingers wrapped around his shaft and slickly stroked his cock back to full hardness; he was further aroused by Tony’s soft moans as he yielded to Steve’s probing touch. 

“So, loverboy,” Tony panted a few minutes later, “how’re we gonna do this?” 

“Let’s you and me get situated first, then the suit can join in.” 

“Alright. Give me a sec to get Mark ready; I can only multitask so much.” Steve watched avidly as the armor donned the strap-on, its precise movements both a tribute to Tony’s engineering skill and a hell of a turn-on at the moment. 

Tony grabbed a couple of pillows and tucked them under his hips, before pulling his knees up to his shoulders. “Get a move on, Cap.” Steve lined himself up and pressed in with slow, shallow strokes, his partner’s body welcoming the intrusion. This simple act of making love would be enough to keep Steve happy for the rest of his life. But Tony was Tony -- never satisfied, always pushing boundaries -- and he’d found a boundary that Steve was all too willing to have pushed. 

“I’m ready.” Steve leaned forward over Tony, spreading his legs to make room for the armor. One gauntlet rested itself on his hip as the slick, blunt end of the dildo pressed up against him. 

“Gonna take this real slow, sweetheart,” Tony said, voice tense with concentration, “since I’m working by sight alone.” 

“I’ll let you know if something doesn’t feel right, I promise.” Steve assured him, even as the first push inside made him inhale sharply. But Tony was as good as his word, and Steve let himself be overwhelmed by the sensation of being tightly sheathed in his beloved while in turn being gradually penetrated. 

“More, Tony, please,” Steve found himself saying, torn between pushing back or thrusting forward to get the friction he so desperately needed. With one final push , the dildo was buried to the hilt inside him; stretching and filling him in the best way. 

“Just relax, loverboy,” Tony crooned, “Let Mark take over and fuck us both.” As he ran his clever hands over Steve’s body, both gauntlets grabbed Steve’s hips tightly. The armor suited deed to word, each thrust pushing him deeper into Tony, making them both moan in wanton delight. 

It was no surprise that Tony came first, a high keen bursting from his lips as he clenched tightly around Steve’s cock. But the armor continued to thrust hard and fast, and Steve wasn’t far behind, his own climax building higher and higher before crashing over him in a wave of ecstasy. One steel-plated arm wrapped around his chest, keeping him from collapsing on Tony as his bones turned to jelly. 

“I have got to show you how this headset works,” Tony murmured as they disengaged from one another, “‘cause I want to be in the middle next time.”


End file.
